One day last June, Clifford Luther served a burger and fries to a man passing through his Saskatchewan diner, Old West Express. Two days later, the man returned and wrote him a check for $10,000. “I thought, They’re good burgers and fries, but they’re not that good,” Luther told CTV News.

The generous tipper was Bob Erb of British Columbia, who won Canada’s $25 million Lotto Max jackpot in November 2012 and has been giving money to people in need. He’s donated to food banks, senior groups, and local fire departments, and he helped 20 people in Terrace, his hometown, get necessary dental care they couldn’t afford.

While flipping burgers that first afternoon, Luther told Erb that his 25-year-old daughter had just been diagnosed with cancer in Vancouver, two provinces and about 1,000 miles away. “It struck a chord. I lost a son four years ago and know the worries a parent has,” says Erb. “I decided on the way home I’d leave him some money so he could go see his daughter.”

A few days later, Erb was on his way back to British Columbia after delivering his father’s ashes to a family cemetery plot in Saskatchewan. He stopped at the diner for another burger, which Luther offered to buy him because Erb had tipped him well just a few days prior. Erb said “no way” and, while the burger was grilling, asked the diner owner for a pen, then scrawled out the check and left it on the counter. “[Luther] looked at the check and couldn’t say anything. He just held his arms out,” Erb says.

Erb, 60, still works construction part-time and hasn’t thought twice about parting with the $7 million he’s given to family, friends, and the community.